Of all lung cancer cases diagnosed in the United States every year, 20-25% are small cell lung cancer (SCLC). Current treatments for small cell lung cancer include surgery, radiation treatment, and chemotherapeutic agents, such as paclitaxel or a combination of etoposide and cisplatin. Despite these treatment options, there is only a 1-5% survival rate after 5 years in patients who have clinically evident metastatic disease upon diagnosis. Glisson et al, Journal of Clinical Oncology, 17(8):2309-2315 (August 1999).
Pre-clinical studies reveal that small cell lung cancers can also be treated with an immunoconjugate comprising a monoclonal antibody and a maytansinoid. Liu et al, Proceedings of the American Association for Cancer Research, 38:29 (abstract 190) (1997). In this study, the maytansinoid was DM1, and the monoclonal antibody was humanized N901. Humanized monoclonal antibody N901 targets CD56, which is expressed on substantially all small cell lung cancers.
There is a need in the art for new and more effective methods for treating cancer. The present invention is directed to these, as well as other, important ends.